Direct drive blower



J. w. TWEEDY DIRECT DRIVE BLOWER Ju y 9,1957

Filed"July,16,"19 54 2 Sheets-Sheet 1 INVEYIQTORV (Iv/v6; IV. Twzeoy vATTORNEYS J. w. TWEEDY; DIRECT DRIVE 12mm Jul 9, 1957 Filed July 16,1954 FIG- 3;

INVENII'O'R JMIK; M. fvzzpr TTORNEYS tent Qfiiice 2,798,659 PatentedJuly 9, 1957 DIRECT DRIVE BLOWER James W. Tweedy, Owosso, MiclL,assignor to Redmond Company, inc Owosso, Mich., a corporation ofMichigan Application July 16, 1954, Serial No. 443,301

4 Claims. (Cl. 230117) The present invention relates to the constructionof a direct drive blower, and in particular to a novel mode of mountingboth the blower wheel and the driving motor therefor.

As the use of blowers in various industrial applications expands,problems of space and expense become more and more critical. It is oftenthe case that in vehicles or in aircraft the blower and its sourceofmotive power, usually an electric motor, must be mounted in veryrestricted spaces andhence the overall size of the conipositeblower-motor combination must be minimized. Moreover, the places wherethese blowers are mounted are not always Well ventilated, andconsequently some means must be provided for cooling the motor ifreliable operation over long periods of time is to be obtained. Inaddition, particularly when blowers are employed in passenger vehiclessuch as private automobiles, themounting of the blower andthe motormust.be'such that as little noise and vibration as possible will be producedby them. It goes without saying that simplification of structure, easeof assemblability and inexpensiveness are also extremely importantfactors, particularly in the case of highly competitive assembliessuchas automobile heating systems.

According to the construction of the present invention a blower-motorcombination unit is produced which takes up no more space than does theblower alone. The construction is such that only a single bearingexternal :of the motor is required, and the motor is readily removableand replaceable in the event of failure thereof. The motor and blowerwheel are mounted as a unit within the blower housing and are insulatedfrom that housing by resilient mounting members, so that vibrationanclnoise is kept to a minimum. The motor is so positioned that wheneverthe blower wheel is rotated fresh air will be drawn over the motor tocool it. The entire structure is exceedingly inexpensive, both from thepoint of view of the cost of parts and from the point of view ofproduction and assembly costs.

To this end the blower housing is provided with the usual apertures onthe sides thereof through which air may enter the housing and pass intothe hollow blower wheel. Mounting brackets, preferably in the form ofspiders, are secured to the housing and extend over the apertures in thesides thereof, the driving motor being received within the housingpreferably coaxially with the blower wheel, one end of the motor havinga projection which is mounted in one of the brackets, the driving shaftextending from the other end of the motor and being received in theother bracket. The shaft passes through the blower wheel, the latterbeing secured thereto in any appropriate manner. It is preferred thatboth the proction on the motor and the bearing be mounted in theirspective brackets via resilient cushioning elements so as inimizevibration and noise. The opening in at least de of the housing, thatside nearest the motor, is

re such that the motor can pass therethrough, and

um is removable in order to facilitate removal and replacement of themotor in the event of necessity for such action. i

To the accomplishment of the above, and to such other objects as mayhereinafter appear, the present invention relates to the structure of ablower-motor combination unit, as defined in the appended claims and asdescribed in this specification, taken together with the accompanyingdrawings, in which:

Fig. 1 is a central vertical cross sectional view of the combinationunit of the present invention;

Fig. 2 is a side elevational view taken from the right hand side of Fig.1; and

Fig. '3 is a side elevational view taken from the left hand side of Fig.1.

The unit comprises a housing generally designated A, a motor generallydesignated B, and a blower wheel generally designated C. i The housingis of conventional shape and comprises a bottom wall 2, side walls 4 anding walls, air being adapted to enter the housing A through 6, end walls8 and 10, the latter having an outlet 12, and a top wall 14. While thesewalls have been separately designated, it will be understood that inmany instances there may be no definite line of demarcation betweenthem, the structural elements of which the walls are made often beingcurved so as to blend gradually from one type of wall to the other, allas is well known in the art of blower housings. T he housing may be previded with feet 16 having apertures 18 so that the unit may be mountedin any appropriate place. Each of the side walls 4 and 6 is providedwith a central aperture 20 and 22 respectively, preferably defined byinwardly flarthe apertures 20 and 22 and air being forced out from thehousing A through the outlet 12 by the action of the blower wheel C.

The blower wheel C is substantially of conventional type and is definedby a pairof rings 24, 26 at each end thereof between which properlyoriented blades 28 are mounted. The wheel C of the present invention isalso provided with a central disk 30 secured to a hub 32 coaxial withthe wheel C. The wheel C is here specifically disclosed as formed of twowheels placed back to back.

The central openings 34 in the rings 24 and 26 at each end of the 'wheelC are sufliciently large sothat the motor B can freely pass therethroughwith appreciable clearance. The motor B is provided with a projectingpart 36 at one end and with a driving shaft 38 extending from the otherend thereof, the shaft 38 being adapted to pass through the bore 40 ofthe hub 32, the latter being op eratively secured to the shaft 38 bymeans of set screw 42. The motor B is of a size such as to be completelyreceived within the housing A and at least partially received within theblower wheel C to one side of the central disk 30 thereof. A bracket 44defined by a plurality of radial arms 46 and a central ring support 48is secured to the end wall 4 by means of bolts 50 and nuts 52 andextends over the aperture 20 in the housing wall 4, air still beingpermitted to pass through the aperture 20 because of the space betweenthe arms 46. A resilient mounting ring 51 is received within the part48, and the projection 36 on the motor B is snugly mounted within thering 51, preferably in a position coaxial with the blower wheel C.

A bracket generally designated 52 is mounted on the housing side wall 6,that bracket also preferably being in the form of a spider defined byradial arms 54 and a central ring-like part 56, the ends of the arms:being secured to the housing side wall 6 by means of bolts 58 and nuts60 extending over the aperture 22 in the side wall 6, air still beingpermitted to pass through the aperture 22 by means of the spaces betweenthe radial arms 24. It is preferred, as here illustrated, that the arms54 be curved so as to extend into the housing A through the aperture 22and into the blower wheel C via the central aperture 34 in the end ring26 thereof, this construction being preferred in order to minimize thelength of the driving shaft 38 to which the wheel C is operativelyconnected, thus minimizing vibration problems which might arise. p

A resilient mounting ring 62 is received within the part 6, a bearingcap 64 is snugly mounted therein, a selfaligning bearing 66 is mountedwithin the bearing cap 64, and the end of the driving shaft 38 isrotatablyv received within the bearing 66, the inner end of the hearingbeing sealed by means of member 68.

It will be apparent from the above descriptionQand from an examinationof the drawings, thatboth the motor B and blower wheel Carecoaxiallymounted within the housing A by means of the. brackets 44 and 52,.thatthe drive of the blower wheel C is direct and positive, that both unitsare resiliently insulated from the housing A by means of the rings 51and 62 in order that noise and vibration should be minimized, that nomore space is taken up by the entire unit than is necessarily taken upby the housing A alone, that only a single external bear ing 66 isrequired for the entire assembly and that, as the blower wheel Cis-rotated, air will be sucked in by it over and through the motor B inorder to cool the latter. If replacement of the motor B is required, itis merely necessary to unscrew the bracket 44 and remove it togetherwith the motor B, first having released the set screw 42 through anyappropriate orifice in the housing A.

The shaft end 38 may merely be pulled out from the bearing 66withoutdisturbing the alignment of that bearing. The motor B is thenreadily removed from the bracket 44, a new motor may be placed therein,and the entire unit reassembled in a simple manner and without requiringany particular skill or any specialequipment. If for any reason thebearing 66 should become defective, it can be replaced in acorrespondingly simple manner. It is to be particularly noted thatbecause of the direct connection between the blower wheel C and theshaft 38, those two elements are always properly aligned with oneanother, and that the brackets 44 and 52, when bolted in place, ensureproper alignment, within acceptable limits, between the blower wheel Cand the housing A, and prevent radial vibration of the blowerwheel Cwhich might otherwise occur through whipping of the shaft 38 if it outerend were unsupported.

While but a single embodiment of the present invention has been heredisclosed, it will be apparent that many variations may be made therein,all within the scope of the following claims.

I claim:

1. A blower-motor combination comprising a blower housing having sidewalls, a blower wheel within said housing between said side walls, amotor having a driving shaft extending from one end thereof, an end ofsaid motor being mounted on one of said housing side walls, the body ofsaid motor being at least partially received inside said wheel, a hublocated intermediate the length of said wheel, said hub operativelyconnecting said wheel to said shaft so that the former is driven by thelatter, the end of said shaft being located inside said wheel, saidother side wall having an element connected thereto which extends intosaid wheel, and a bearing carried by said element within which saidshaft end is rotatably received, said bearing and said mounting for saidend of said motor comprising substantially the sole support for saidblower wheel and motor within said housing, and said hub comprisingsubstantially the sole support of said blower wheel on said motor.

2. The combination of claim 1, in which said bearing is of theself-aligning type.

3. A blower-motor. combination comprising a blower housing, a blowerwheel within said housing, said housing having side walls with air entryapertures in line with said wheel, a motor having a driving shaftextending from one end thereof, and a part projecting from the other endthereof, a spider extending over the aperture in one of said housingside walls in which spider said motor part is received and mounted, thebody of said motor being at least partially received inside said wheel,a hub located intermediate the length of said wheel, said huboperatively connecting said wheel to said shaft so that the former isdriven by the latter, the end of said shaft being located inside saidwheel, a spider extending over the aperture in the other of said housingwalls and terminating inside said wheel, and a bearing carried by saidspider within which said shaft is rotatably received, said bearing andsaid spider comprising substantially the sole support for said blowerwheel and motor within said housing, and

.said hub comprising substantially the sole support of said blower wheelon said motor.

4. The combination of claim 3, in which said bearing is of theself-aligning type.

References Cited in the file of this patent UNITED STATES PATENTS1,921,218 Colby Aug. 8, 1933 1,935,538 Baumann Nov. 14, 1933 2,297,049Cotton et a1 Sept. 29, 1942 2,476,515 Stevens July 19, 1949 2,482,847Goodman Sept. 27, 1949 2,661,894 Stevenson et al Dec. 8, 1953 2,686,630Burrowes Aug. 17, 1954 I l 1 l

